What code or command allows me to know from a final value, which vector originated or produced that final value?
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I have an "rguard" vector composed of 20 sub-vectors, of 10 elements each. Choosing a vector of 10 elements, I pass it to a shift and I get 10 vectors of 10 elements each. Later that vector introduced it to a formula and I get a vectro "SLL1" 10 values, a value per vector of 10 elements, later these values (10) I introduce them to another formula and I get 10 probability values. The question is: What code or command allows me to know from that probability value, which vector originated or produced?
4 Comments
John D'Errico
on 15 Jan 2018
Edited: John D'Errico
on 15 Jan 2018
Huh? A totally confusing question, and not even about MATLAB at all. Likely that means Ricardo is also totally confused, as the inability to pose a clear, cogent question tends to imply the person asking really does not understand the problem.
Sometimes the issue is the asker does understand what they are asking, but for some reason they have tried to make the question too abstract, but just made it confusing as hell.
If you have assigned probabilities to each vector that imply the probability a result originated from that vector, then you choose the one with maximum probability. WTP?
help max
Walter Roberson
on 15 Jan 2018
What you are asking for is not generally possible, and when possible is not generally practical (consider for example asking which input combinations "cause" a particular output bit in AES-256 cryptography). It might be possible for some code, but that could only be known by having the code available and tracing the values back through.
Sometimes a workable approach is to use the Symbolic Toolbox to pass a vector or matrix of symbolic values through the code, and then the output would be symbolic formula instead of numeric values; examining the formulas can show you which part of the input go into making up a particular output.
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